Molecular mechanisms of oxidative stress-related neonatal jaundice.

Oxidative stress is a pathological condition characterized by an overload of oxidant products, named free radicals, which are not well counteracted by antioxidant systems. Free radicals induce oxidative damage to many body organs and systems. In neonatal red blood cells, free-radical mediated-oxidative stress leads to eryptosis, a suicidal death process of erythrocytes consequent to alteration of cell integrity. Neonatal red blood cells are targets and at the same time generators of free radicals through the Fenton and Haber-Weiss reactions. Enhanced eryptosis in case of oxidative stress damage may cause anemia if the increased loss of erythrocytes is not enough compensated by enhanced new erythrocytes synthesis. The oxidative disruption of the red cells may cause unconjugated idiopathic hyperbilirubinemia in neonates. High levels of bilirubin are recognized to be dangerous for the central nervous system in newborns, however, many studies have highlighted the antioxidant function of bilirubin. Recently, it has been suggested that physiologic concentration of bilirubin correlates with higher antioxidant status while high pathological bilirubin levels are associated with pro-oxidants effects. The aim of this educational review is to provide an updated understanding of the molecular mechanisms underlying erythrocyte oxidant injury and its reversal in neonatal idiopathic hyperbilirubinemia.

FOXA2 prevents hyperbilirubinaemia in acute liver failure by maintaining apical MRP2 expression.

OBJECTIVE: Multidrug resistance protein 2 (MRP2) is a bottleneck in bilirubin excretion. Its loss is sufficient to induce hyperbilirubinaemia, a prevailing characteristic of acute liver failure (ALF) that is closely associated with clinical outcome. This study scrutinises the transcriptional regulation of MRP2 under different pathophysiological conditions. DESIGN: Hepatic MRP2, farnesoid X receptor (FXR) and Forkhead box A2 (FOXA2) expression and clinicopathologic associations were examined by immunohistochemistry in 14 patients with cirrhosis and 22 patients with ALF. MRP2 regulatory mechanisms were investigated in primary hepatocytes, Fxr -/- mice and lipopolysaccharide (LPS)-treated mice. RESULTS: Physiologically, homeostatic MRP2 transcription is mediated by the nuclear receptor FXR/retinoid X receptor complex. Fxr-/- mice lack apical MRP2 expression and rapidly progress into hyperbilirubinaemia. In patients with ALF, hepatic FXR expression is undetectable, however, patients without infection maintain apical MRP2 expression and do not suffer from hyperbilirubinaemia. These patients express FOXA2 in hepatocytes. FOXA2 upregulates MRP2 transcription through binding to its promoter. Physiologically, nuclear FOXA2 translocation is inhibited by insulin. In ALF, high levels of glucagon and tumour necrosis factor α induce FOXA2 expression and nuclear translocation in hepatocytes. Impressively, ALF patients with sepsis express low levels of FOXA2, lose MRP2 expression and develop severe hyperbilirubinaemia. In this case, LPS inhibits FXR expression, induces FOXA2 nuclear exclusion and thus abrogates the compensatory MRP2 upregulation. In both Fxr -/- and LPS-treated mice, ectopic FOXA2 expression restored apical MRP2 expression and normalised serum bilirubin levels. CONCLUSION: FOXA2 replaces FXR to maintain MRP2 expression in ALF without sepsis. Ectopic FOXA2 expression to maintain MRP2 represents a potential strategy to prevent hyperbilirubinaemia in septic ALF.

Clinical characteristics and liver profiles of Dubin-Johnson syndrome in neonates: Multicenter retrospective study.

OBJECTIVES: Dubin-Johnson syndrome (DJS) is a rare benign autosomal recessive disorder characterized by cholestasis in neonates. The aim of the present study was to describe the clinical characteristics, hepatic profiles, histopathology, gene mutations, and treatment outcomes of neonatal DJS. MATERIAL AND METHODS: A multicenter retrospective study was undertaken with patients who had DJS. The authors identified DJS in neonates and reviewed medical records for details. The diagnosis of DJS was based on the presence of unexplained prolonged conjugated hyperbilirubinemia and presence of a mutation in the ATP Binding Cassette Subfamily C Member 2 (ABCC2) gene detected in genomic DNA extracted from circulating blood cells. RESULTS: Eleven children with DJS were identified in the study. The study population comprised eight males and three females. The median age at presentation was 21 days. Dysmorphic features were not recorded in any of the patients. Cholestasis, high serum bile acids, and normal transaminase levels were found in all patients (100%). Serum alkaline phosphatase and gamma glutamyl transferase were elevated in four patients (36%). Hypoalbuminemia and coagulopathy were not noted in these patients. Consanguinity was present in nine patients (82%). All patients had normal abdominal ultrasound findings. Genetic molecular testing showed that 82% of the patients reported a pathogenic variant of the ABCC2 gene defect with the same variant c.2273G>T (Gly 758 val) chromosome 10. All patients were alive without liver transplantation. CONCLUSIONS: This is the largest study worldwide describing that neonatal DJS is a benign cholestatic disease with favorable outcomes. Low-grade direct hyperbilirubinemia, normal transaminases, and elevated serum bile acids are the main characteristic findings of DJS.

Yinzhihuang Oral Liquid Ameliorates Hyperbilirubinemia Induced by δ-Aminolevulinic Acid and Novobiocin in Neonatal Rats.

Yinzhihuang oral liquid (YZH) is a traditional Chinese medicine that has been widely used in Asia to prevent and treat neonatal hyperbilirubinemia, but the published preclinical studies on its anti-hyperbilirubinemia effect are conducted in adult animals, partly due to the lack of preclinical neonatal hyperbilirubinemia animal models. In the present study, we tested six reagents to induce hyperbilirubinemia in neonatal rats, and established two appropriate neonatal hyperbilirubinemia rat models by subcutaneous injection of δ-Aminolevulinic acid (ALA, 200 mg/kg) or novobiocin (NOVO, 200 mg/kg). Oral treatment of YZH (80, 160 and 320 mg/kg) significantly decreased serum conjugated bilirubin levels in ALA-treated neonatal rats and serum unconjugated bilirubin levels in NOVO-treated neonatal rats, respectively. Additionally, pre-treatment of YZH also prevented the increase of serum bilirubin levels in both ALA- and NOVO-treated rats. Mechanistically, YZH significantly up-regulated the mRNA expression of genes involved in hepatic bilirubin disposition (organic anion-transporting polypeptide 1b2, Oatp1b2; multidrug resistance-associated protein 2, Mrp2) and bilirubin conjugation (UDP-glucuronosyltransferase 1a1, Ugt1a1). Additionally, YZH up-regulated the mRNA expression of cytochrome P450 1A1 (Cyp1a1), the target gene of aryl hydrocarbon receptor (AhR), and increased the nuclear protein levels of AhR in livers of neonatal rats. YZH and its two active ingredients, namely baicalin (BCL) and 4'-hydroxyacetophenone (4-HT), up-regulated the mRNA expression of AhR target genes (CYP1A1 and UGT1A1) and increased nuclear protein levels of AhR in HepG2 cells. In conclusion, the present study provides two neonatal hyperbilirubinemia animal models and evaluates the anti-hyperbilirubinemia effect and mechanisms of YZH in neonatal animals.

Hyperbilirubinemia in pediatrics: Evaluation and care.

Hyperbilirubinemia is a common laboratory finding for children, especially in infancy. It represents a broad range of diagnoses from benign physiologic changes to severe systemic illness. This paper addresses the evaluation and differential diagnosis of hyperbilirubinemia for infants and older children based on the most recent guidelines published by the American Academy of Pediatrics (AAP) (1), the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) and the European Society for Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) (2).

Periportal thickening on magnetic resonance imaging for hepatic fibrosis in infantile cholestasis.

BACKGROUND: Untreated neonatal cholestasis can progress to liver cirrhosis and end stage liver disease in infancy due to prolonged hepatocyte and biliary tree injury and may require liver transplantation. Therefore, non-invasive evaluation of hepatic fibrosis is important in infants with cholestasis. AIM: To investigate the usefulness of periportal thickening (PT) measured on liver magnetic resonance imaging (MRI) for the assessment of hepatic fibrosis in infants with cholestasis including biliary atresia (BA). METHODS: This retrospective study included infants less than 6 mo who underwent liver MRI and biopsy for the evaluation of infantile cholestasis. PT and spleen size were measured on MRI. Serologic assessment was based on aspartate transaminase to platelet ratio index (APRI). The grade of histopathologic fibrosis was assessed by the METAVIR grading system. Correlation and diagnostic performance of PT, normalized spleen size ratio (SR, using the upper normal size limit), and APRI for diagnosing hepatic fibrosis were obtained by receiver-operating characteristic (ROC) curve analysis. RESULTS: A total of 155 patients were included, 110 of which were diagnosed with BA. Mean age at the time of MRI was 57.6 ± 34.4 d. There were positive correlations between fibrosis grade and PT and SR, even after adjusting age (all, P < 0.001). For the diagnosis of significant fibrosis (METAVIR grade F2-F4), the area under the ROC curve was 0.899 (95%CI: 0.840-0.941) for PT (cutoff, 4.2 mm), which was higher than 0.741 (95%CI: 0.664-0.808) for SR and 0.712 (95%CI: 0.634-0.782) for APRI (both, P < 0.001). For the diagnosis of cirrhosis (F4), the area under the ROC curve was the highest with SR as 0.790 (95%CI: 0.718-0.852). CONCLUSION: Liver MRI findings of PT and SR are useful to assess clinically significant hepatic fibrosis (F2 and higher) in infants with cholestasis including BA.

Development and validation of an ambulatory piglet model for short bowel syndrome with ileo-colonic anastomosis.

IMPACT STATEMENT: Short bowel syndrome is associated with significant comorbidities and mortality. This study is important as unlike current systems, it provides a validated piglet model which mirrors anatomical, histological, and serological characteristics observed in human SBS. This model can be used to advance knowledge into mechanistic pathways and therapeutic modalities to improve outcomes for SBS patients. This study is novel in that in addition to significant reduction in the remnant bowel and noted liver disease, we also developed a method to emulate ileocecal valve resection and described gut adaptive responses which has important clinical implications in humans.

Incidence and predictors of treatment-related conjugated hyperbilirubinemia during early treatment phases for children with acute lymphoblastic leukemia.

Conjugated hyperbilirubinemia (CHB) and liver transaminase elevation are known complications of acute lymphoblastic leukemia (ALL) therapy, but host risk factors are poorly understood. Among 373 children diagnosed with ALL between 2011 and 2016, clinically significant CHB and transaminase elevation were observed in 15 (4.0%) and 12 (3.2%) children, respectively, during induction and consolidation. Body mass index ≥95th percentile (odds ratio 9.20, 95% confidence interval 2.56-32.96) was the only host factor independently associated with CHB, and no host factors were associated with transaminase elevation. Obese patients warrant closer monitoring of hepatic function to facilitate early intervention prior to the development of severe, adverse hepatic events.

Analysis of the UGT1A1 Genotype in Hyperbilirubinemia Patients: Differences in Allele Frequency and Distribution.

OBJECTIVE: The spectrum of UDP-glucuronyl transferase A1 (UGT1A1) variants in hereditary unconjugated hyperbilirubinemia varies markedly between different ethnic populations. This study evaluated the UGT1A1 genotypes in hyperbilirubinemia patients from southeastern China. METHODS: We enrolled 60 patients from southeastern China (44 men and 16 women; age range: 3-76 years) with unconjugated hyperbilirubinemia and performed genetic analysis of the UGT1A1 gene by direct sequencing. RESULTS: For patients with Gilbert syndrome, 85% (47/55) harbored pathogenic variants of UGT1A1⁎60. Both UGT1A1⁎28 and UGT1A1⁎81 were detected in the promoter region of UGT1A1. Additionally, 83% (20/24) of patients with Gilbert syndrome heterozygous for UGT1A1⁎60 had an association with heterozygous variation of UGT1A1⁎28 or UGT1A1⁎81, while 91% (21/23) of Gilbert syndrome patients homozygous for UGT1A1⁎60 had biallelic variations of UGT1A1⁎28 and UGT1A1⁎81. We detected 213 UGT1A1 allelic variants, including six novel variations, with the most frequent allele being the UGT1A1⁎60, followed by UGT1A1⁎28 and UGT1A1⁎6. All of the patients showed multiple sites of variants in UGT1A1; however, variation number was not associated with bilirubin levels (P>0.05). CONCLUSIONS: The spectrum of UGT1A1 variants in southeastern Chinese patients was distinct from other ethnic populations. Our findings broaden the knowledge concerning traits associated with UGT1A1 variants and help profile genotype-phenotype correlations in hyperbilirubinemia patients.

Hyperbilirubinemia Induces Pro-Apoptotic Effects and Aggravates Renal Ischemia Reperfusion Injury.

AIMS: Hyperbilirubinemia is associated with postoperative acute kidney injury in patients undergoing cardiac surgeries. A high concentration of bilirubin could induce oxidative stress and cell apoptosis. The aim of this study was to investigate whether hyperbilirubinemia aggravated the renal tubule cells injury and the pro-apoptotic potential of bilirubin on renal ischemia reperfusion injury (RIRI). METHODS: The human proximal tubular epithelial cell line HK-2 cells were challenged with a gradient concentration of bilirubin for 24 h. Cell injury was assessed by flow cytometry and MTT assay. Bilirubin was injected intraperitoneally into male Sprague-Dawley rats once every 12 h (100 mg/kg), 3 times in total. The same solvent volume without bilirubin powder was used as vehicle in non-bilirubin injection groups. The RIRI surgical procedure was a bilateral renal pedicles clamping (45 min) followed by 30 h reperfusion. The rats were divided into 4 groups: negative control (NC), similar surgical procedures without clamping; Bil, bilirubin injection for 36 h, then rats were sacrificed; RIRI, RIRI surgical procedures; Bil + RIRI, RIRI applied 6 h later than the first bilirubin injection, rats were sacrificed after another 30 h. RESULTS: In vitro, bilirubin induced cell apoptosis and significantly decreased the cell viability of HK-2 cells. Bilirubin induced the active caspase 3 and phosphorylation of p38 in HK-2 cells. In vivo, serum creatinine was higher in Bil + RIRI compared with RIRI (p < 0.01). The tubular injury scores of hematoxylin and eosin and tubular necrosis scores of periodic acid-Schiff were higher in Bil + RIRI than these in RIRI (All p < 0.05). The number of Tunel-positive nuclei was higher in Bil + RIRI compared to RIRI (p < 0.001). The active caspase 3 and phosphorylation of p38 were higher and the Bcl2 was lower in Bil + RIRI compared to RIRI. Moreover, the apoptosis level was higher in Bil compared to NC. CONCLUSIONS: Our results reveal that the hyperbilirubinemia induces pro-apoptotic effects and aggravates RIRI.

Clinical Value of Inflammation-Based Prognostic Scores to Predict the Resectability of Hyperbilirubinemia Patients with Potentially Resectable Hilar Cholangiocarcinoma.

BACKGROUND: We aimed to examine whether inflammation-based prognostic scores could predict tumor resectability in a cohort of hilar cholangiocarcinoma patients with preoperative hyperbilirubinemia. We also sought to investigate the prognostic factors associated with overall survival in the subgroup of patients with an R0 resection. METHODS: A total of 173 patients with potentially resectable hilar cholangiocarcinoma, as judged by radiological examinations, were included. The potential relationship of the Glasgow prognostic score (GPS), modified GPS, platelet lymphocyte ratio (PLR), neutrophil lymphocyte ratio (NLR), prognostic nutritional index (PNI), and prognostic index (PI) with tumor resectability were investigated using univariate and multivariate analysis. RESULTS: Among the 173 patients, 134 had R0 resection margins. Univariate analysis identified that patients with PLR ≥ 150, NLR ≥ 3, PNI ≥ 45, GPS (0.1/2), modified GPS (0.1/2), preoperative CA 125 > 35 U/mL, and a tumor size ≥ 3 cm were more likely to have unresectable tumors. Multivariate analysis indicated that tumor size ≥ 3 cm (OR = 2.422, 95% CI: 1.053-5.573; P = 0.037), PLR ≥ 150 (OR = 3.324, 95% CI: 1.143-9.667; P = 0.027), preoperative CA 125 > 35 U/mL (OR = 3.184, 95% CI: 1.316-7.704; P = 0.010), and GPS (0.1/2) (OR = 2.440, 95% CI: 1.450-4.107; P = 0.001) were independent factors associated with tumor resectability. In selected patients with an R0 resection in this cohort, nodal status (P = 0.010) and tumor differentiation (P = 0.025) were predictive of poor survival outcome. CONCLUSION: Patients with higher GPS, CA 125, and PLR levels, and a larger tumor size, tend to have unresectable tumors even if they were judged as potentially resectable using preoperative radiological examinations.

"Gilbert's-like" syndrome as part of a spectrum of persistent unconjugated hyperbilirubinemia in post-chronic hepatitis patients.

Gilbert's syndrome (GS) patients present with remittent unconjugated hyperbilirubinemia. In this study, we investigated the correlation between polymorphisms in the gene encoding UDP-glucuronosyltransferase, UGT1A1, and the development of unconjugated hyperbilirubinemia in clinical GS and post-hepatitis hyperbilirubinemia. Blood samples were collected from 285 patients, including 85 patients who were clinically diagnosed with GS, 70 patients who had indirect hyperbilirubinemia during the recovery period of chronic liver diseases, 109 patients with normal hepatic function and 21 chronic active hepatitis patients. All samples were tested for the presence of the *28/*6 UGT1A1 genotype by pyrosequencing. Compared with the GS-control group, a significant difference in variations of the UGT1A1*28/*6 allele gene was found in GS patients. The post-hepatitis group showed a significant difference in the UGT1A1*28/*6 allele gene frequency distribution relative to that in the hepatitis control group. There were no significant differences between the GS group and post-hepatitis group in the distribution of the UGT1A1*28/*6 allele gene frequency and UGT1A1 diplotypes. UGT1A1*28/*6 gene polymorphisms in patients who had indirect hyperbilirubinemia while recovering from chronic liver diseases presented similar patterns as those seen for GS patients. These findings suggest that a "Gilbert's-like" syndrome might be part of the spectrum of persistent unconjugated hyperbilirubinemia in post-chronic hepatitis patients.

All That Glitters Yellow Is Not Gold: Presentation and Pathophysiology of Bile Cast Nephropathy.

BACKGROUND: Acute kidney injury (AKI) often manifests in patients with liver disease because of a prerenal cause and presents as acute tubular necrosis or hepatorenal syndrome. Distinguishing between these entities is important for prognosis and treatment. Some patients may develop AKI related to their underlying liver disease: for example, membranoproliferative glomerulonephritis or IgA nephropathy. Bile cast nephropathy is an often ignored differential diagnosis of AKI in the setting of obstructive jaundice. It is characterized by the presence of bile casts in renal tubules, which can possibly cause tubular injury through obstructive and direct toxic effects. Thus, AKI in patients with liver disease may have a structural component in addition to a functional one. METHODS: In this study, we describe 2 patients with severe hyperbilirubinemia who developed AKI and underwent a kidney biopsy that revealed bile casts in tubular lumens, consistent with bile cast nephropathy. RESULTS: One patient was treated aggressively for alcoholic hepatitis and required hemodialysis for AKI. The second patient was treated conservatively for drug-induced liver injury and did not require dialysis. Both patients saw a reduction in their bilirubin and creatinine toward baseline. CONCLUSION: Bile cast nephropathy is an important pathological entity that may account for the renal dysfunction in some patients with liver disease. It requires kidney biopsy for diagnosis and may often be overlooked given the scarcity of kidney biopsy in this particular clinical setting. The etiology is multifactorial, and it is often difficult to predict without the aid of a renal biopsy.

Persistence of hepatic fibrosis in pediatric intestinal failure patients treated with intravenous fish oil lipid emulsion.

BACKGROUND: Pediatric intestinal failure (PIF) is a life-altering chronic condition with significant morbidity and mortality. Omegaven® therapy has been used to treat children with advanced intestinal failure associated liver disease. Our objective was to determine the evolution of hepatic fibrosis in PIF patients who received Omegaven® and describe their clinical outcome. METHODS: A retrospective review in PIF patients who received Omegaven® was performed. Patients were included if they had liver biopsies completed before Omegaven® therapy and after resolution of hyperbilirubinemia. Biopsy results were evaluated to determine the degree of fibrosis, inflammation, and cholestasis. Clinical and biochemical data was collected. RESULTS: Six patients were identified. Assessment of fibrosis at last follow-up demonstrated improvement in 2 patients and progression or stable fibrosis in 4/6. All patients demonstrated reduction in cholestasis and inflammation. One patient received a liver/intestine transplant and a second is listed, both of them with progressive fibrosis. One patient achieved full enteral nutrition, while the rest remain partially parenteral nutrition dependent. CONCLUSION: Use of Omegaven® is associated with reduced cholestasis and inflammation, but with persistence or worsening of fibrosis in some patients. A subset of patients with progressive fibrosis may develop portal hypertension and progressive liver disease.

Systems pharmacology modeling of drug-induced hyperbilirubinemia: Differentiating hepatotoxicity and inhibition of enzymes/transporters.

Elevations in serum bilirubin during drug treatment may indicate global liver dysfunction and a high risk of liver failure. However, drugs also can increase serum bilirubin in the absence of hepatic injury by inhibiting specific enzymes/transporters. We constructed a mechanistic model of bilirubin disposition based on known functional polymorphisms in bilirubin metabolism/transport. Using physiologically based pharmacokinetic (PBPK) model-predicted drug exposure and enzyme/transporter inhibition constants determined in vitro, our model correctly predicted indinavir-mediated hyperbilirubinemia in humans and rats. Nelfinavir was predicted not to cause hyperbilirubinemia, consistent with clinical observations. We next examined a new drug candidate that caused both elevations in serum bilirubin and biochemical evidence of liver injury in rats. Simulations suggest that bilirubin elevation primarily resulted from inhibition of transporters rather than global liver dysfunction. We conclude that mechanistic modeling of bilirubin can help elucidate underlying mechanisms of drug-induced hyperbilirubinemia, and thereby distinguish benign from clinically important elevations in serum bilirubin.

An Increased Genotoxic Risk in Lymphocytes from Phototherapy-Treated Hyperbilirubinemic Neonates.

BACKGROUND: Phototherapy is believed to be a safe method for the management of hyperbilirubinemia. However, there are some controversial issues regarding the genotoxic effects of phototherapy on DNA. The aim of this study was to investigate morphologically both phototherapy-induced DNA double-strand breaks (DSBs) and apoptosis in lymphocytes derived from jaundiced and non-jaundiced neonates. METHODS: Newborns were divided into three groups, including phototherapy-treated (PT, n=30) jaundiced newborns with total serum bilirubin (TSB) levels >15 mg/dl, non-treated jaundiced newborns (C+, n=27), as positive, as well as healthy negative (C-, n=30) controls with TSB levels ranging from 10 and 15 mg/dl and less than 5 mg/dl, respectively. Lymphocytes were isolated from whole blood samples by Ficoll-isopaque density gradient centrifugation and then assessed for DNA damage and apoptosis before and 24 hours after incubation at 37°C in 5% CO2 using the neutral comet assay. RESULTS: DSB levels were significantly much higher in the PT group compared to the controls before incubation but decreased remarkably after the incubation period. As expected, no statistical differences were found between the two control groups before and after incubations. The frequency of apoptotic cells showed no significant differences among all the three groups before incubation; however, it was significantly increased in the PT group after incubation. CONCLUSION: It seems that phototherapy in jaundiced infants is able not only to induce apoptosis in newborn lymphocytes but also to affect indirectly DNA integrity.

Hyperbilirubinemia Protects against Aging-Associated Inflammation and Metabolic Deterioration.

Mild constitutive hyperbilirubinemia is associated with a reduced risk of cardiovascular diseases, diabetes, and cancer. Since these pathologies are associated with aging, inflammation, and oxidative stress, we investigated whether hyperbilirubinemia interferes with ROS homeostasis in cell cultures and with inflammation, senescence, and mitochondrial dysfunction in aged rats. Human embryonic kidney cells and rat primary fibroblasts showed a dose-dependent decrease in the ratio of oxidized/reduced glutathione, intracellular H2O2 levels, and mitochondrial ROS production, with increasing bilirubin concentrations in the culture media. Compared to their normobilirubinemic siblings, aged hyperbilirubinemic Gunn rats showed significantly smaller amounts of visceral fat, better glucose tolerance, and decreased serum levels of proinflammatory cytokines TNFα, IL-1ß, and IL-18. Simultaneously, livers from Gunn rats showed decreased expression of senescence markers and cell cycle inhibitors p21 and p16. Mitochondria from aged Gunn rats showed higher respiration and lower H2O2 production compared to controls. In conclusion, we demonstrated that mildly elevated serum bilirubin is generally associated with attenuation of oxidative stress and with better anthropometric parameters, decreased inflammatory status, increased glucose tolerance, fewer signs of cellular senescence, and enhanced mitochondrial function in aged rats.

Early Bactericidal Activity of AZD5847 in Patients with Pulmonary Tuberculosis.

AZD5847 is an oxazolidinone antibiotic with in vitro activity against Mycobacterium tuberculosis The objective of this study was to evaluate the antimycobacterial activity, safety, and pharmacokinetics of AZD5847 in patients with pulmonary tuberculosis. Groups of 15 treatment-naive, sputum smear-positive adults with pulmonary tuberculosis were randomly assigned to receive AZD5847 at one of four doses (500 mg once daily, 500 mg twice daily, 1,200 mg once daily, and 800 mg twice daily) or daily standard chemotherapy. The primary efficacy endpoint was the mean daily rate of change in the log10 number of CFU of M. tuberculosis per milliliter of sputum, expressed as the change in log10 number of CFU per milliliter of sputum per day. The mean 14-day activity of the combination of isoniazid, rifampin, ethambutol, and pyrazinamide (-0.163 log10 CFU/ml sputum/day; 95% confidence interval [CI], -0.193, -0.133 log10 CFU/ml sputum/day) was consistent with that found in previous studies. AZD5847 at 500 mg twice daily significantly decreased the number of CFU on solid medium (-0.039; 95% CI, -0.069, -0.009; P = 0.0048). No bactericidal activity was detected at doses of AZD5847 of 500 mg once daily (mean early bactericidal activity [EBA], 0.02 [95% CI, -0.01, 0.05]), 1,200 mg once daily (mean EBA, 0.02 [95% CI, -0.01, 0.05]), and 800 mg twice daily (mean EBA, 0.02 [95% CI, -0.01, 0.05]). AZD5847 at doses of both 500 mg and 800 mg twice daily also showed an increase in the time to a positive culture in MGIT liquid culture medium. Two serious adverse events (grade 4 thrombocytopenia and grade 4 hyperbilirubinemia) occurred in patients receiving AZD5847 at higher doses. AZD5847 dosed twice daily kills tubercle bacilli in the sputum of patients with pulmonary tuberculosis and has modest early bactericidal activity. (This study has been registered at ClinicalTrials.gov under registration no. NCT01516203.).